Issue

After upgrading PHP from 5.4.16 to 5.6.36 web pages that contain PEAR mail scripts fail to load with Error 500 (Internal Server Error)

After enabling display_errors in PHP settings following errors were displayed:

Warning: require_once(Mail.php): failed to open stream: No such file or directory in /var/www/vhosts/domain.com/httpdocs/forms/contact_form.php on line 18

Fatal error: require_once(): Failed opening required ‘Mail.php’ (include_path=’.:/opt/plesk/php/5.6/share/pear’) in /var/www/vhosts/domain.com/httpdocs/forms/contact_form.php on line 18

Resolution

Issue was resolved by adding PEAR install path (/usr/share/pear) to include_path in PHP settings.

June 2018
Plesk Onyx 17
CentOS 7
PHP
PEAR Mail